Submitted photographs must be created in the "TWAN style" — showing both the Earth and the sky — by combining elements of the night sky (e.g., stars, planets, the Moon or celestial events) set against the backdrop of a beautiful, historic, or notable location or landmark. This style of photography is called "landscape astrophotography". This is similar to general "Nightscape Photography" but with more attention to the sky, astronomical perspectives, and celestial phenomena.